Dispatches from Brazil: Diving for Coral

Dispatches from Brazil: Diving for Coral

December 01, 2008

By Sara LaJeunesse
Research Penn State

In this last of three dispatches from Northeast Brazil, Todd LaJuenesse and colleagues dive for coral in in João Pessoa. Researchers at Penn State, the University of Georgia and Universidade Federal de Campina Grande are embarking on a quest to document the uniqueness of Brazil's coral species by studying the symbiotic algae that they require to survive. In addition, they will investigate the evolutionary biology of the coral-algal symbiosis to see if they can uncover secrets about the organisms' ancient histories and their potential to withstand the ravages of climate change.

Dispatch 3

This morning we wake early to get a head start on what will be a long day of fieldwork. We meet up with two Brazilian colleagues, Cristiane Francisca da Costa, a professor of biology at the Universidade Federal de Campina Grande, and Roberto Sassi, director of the Núcleo de Estudos e Pesquisas de Recursos do Mar (NEPREMAR) at the Universidade Federal da Paraíba. These two know where to find the greatest diversity of corals and other Symbiodinium -containing creatures in the region, and they have arranged for a boat to take us there.

When we arrive at the beach, I am amused to find that the boat is not a research vessel, but instead an old, wooden fishing boat decorated with a painting of Saint Peter, the patron saint of fishermen. I am also surprised to find that it is moored about 40 yards offshore, rather than at a pier. We’ll have to wade out with our things held high above our heads to get to it.

We will pay the boat’s owner, Iran, to take us to two different reefs. A jolly fellow with a dark tan and a big belly, Iran speaks decent English, so he and I spend some time chatting. I ask him if he has seen any sharks lately and he shows me a large scar on his left elbow. “There are many dangerous sharks in these waters,” he says. This, however, is followed by a smirk and a giggle. I think he is pulling my leg.

After half an hour, we arrive at our first location. The water here is a little cloudy, so I decide to swim rather than dive. Todd and Cristiane, however, must dive so that they can access the corals below. The two biologists spend about an hour in the water, returning to the boat with eight different species.

“At least four of these I have never collected before,” says Todd. “By adding them to the datasets of species we have collected elsewhere in the world, we can gain a better understanding of the total amount of diversity of Symbiodinium on the planet. We can also learn how this diversity is distributed, and how the host-symbiont associations have changed over time. Understanding how these symbiotic systems evolve can help us to predict how they will respond to major environmental stresses such as global warming.”

With everyone back on the boat, we make our way to the next location. This time, the reef is much larger and the water is clearer. Again Todd and Cristiane strap on their dive gear and step out over the boat’s side, landing with a splash. Their plan is to swim around the edge of the reef, looking for corals at a depth of about 12 feet, and then to swim over the top of the reef, which lies just a few feet under the water.

Because the water is so shallow and clear, Bill, Susan, and I decide to snorkel rather than dive. We will be able to see nearly as much as the divers do, and we won’t have to fuss with a bunch of gear. I decide to spend my time swimming on top of the reef where I hope the water is too shallow for sharks.

Under the Sea

From the boat, the reef looks like a giant creature crouched at the bottom of the sea. And it is a giant creature, in a way. Most corals reproduce by cloning themselves until they have formed enormous colonies of genetically identical individuals.

The scene from below the water, however, is completely different. What looked like a dark blob from the surface is a bright and sunny underwater paradise. Tiny black fish with purple faces dart in and out of the reef’s crevices; electric-blue tangs skirt the reef’s edge; and goby fish with their comical faces and protruding eyes attempt to blend in with the sand and rocks.

I see bits of live coral here and there, but most of the reef is topped with a lush, green plant that sways back and forth in the current. Bill tells me that this is green algae and its presence here signifies that the area contains nutrients, likely from the nearby river that passes through sugar cane fields on its way to the ocean.

Susan and I spend about an hour snorkeling, and although the water is about 86 degrees Fahrenheit, we feel a little cold, so we decide to get out. As we wait for the biologists to finish their work, Iran tells us stories. “I love the sea more than I love my own mother,” he says, “because even though I am a grown man, she feeds me, cleans me, and rocks me to sleep.”

Iran specializes in capturing lobsters, but he also uses a harpoon to catch fish. So many of Brazil’s coastal citizens make a living this way, and I realize that this is why the only creatures I saw while snorkeling were small reef fish. Iran tells us that when he was a boy, the ocean contained many more fish.

After a while, the research team returns to the boat. This time, they don’t have much to show for their efforts. Although the team did not find any new species at this site, they are happy to have replicate samples from two different sites. The lack of additional species at the second site also might indicate that the scientists found all of the possible symbiotic invertebrates in the area.

At Work in the Laboratory

After dinner, we head to the Universidade Federal da Paraíba to process the samples before they die. Several of Cristiane’s students have come to help and to learn from Todd and Bill how to prepare the samples for further analysis. While Todd and Bill have acquired a great deal of information from Cristiane and Roberto about Brazil’s corals and other symbiotic organisms, the Brazilians stand to benefit as well from this collaboration. Todd and Bill are among the world’s top experts in this field, and they have developed new technique to analyze the data.

The group identifies the species of corals in today’s catch and separates them into vials containing a special preservative. As they sort through the specimens, Todd explains to the Brazilians some techniques for rapidly identifying symbiont species for ecological studies, while Bill explains how they can dry out samples and weigh them. The heavier they are, he says, the more Symbiodinium they contain, and the healthier they are.

Reflections

It is after 9 p.m. by the time we leave the laboratory. On our way back to the hotel, we reflect on the day’s work. Todd talks about how pleased he is to have collected some new species of coral, which he thinks contain new species of Symbiodinium, as well.

“The corals we found were scattered among the ruins of what was once a vast and vibrant reef,” says Todd. Coral reefs around the world are suffering from human impacts such as pollution and global warming. In northeastern Brazil, the corals were scraped from the reefs over 100 years ago, and piled on the beaches where they were burned to make lye for use in cement. Since that time, the coral reefs have recovered somewhat, and although their abundance remains low, the number of species is high.

The team says that they would like to work with Cristiane and Roberto in the future to investigate some of Brazil’s other reefs, especially those that are located much farther away from the land. Many of these reefs are rumored to contain vast numbers of thriving corals.

As we arrive at the hotel and begin to head to our separate rooms, Susan tells me that Iran had asked her if she thought that I might like to remain in Brazil with him. Laughing, I respond that although I wouldn’t mind staying in Brazil a little longer, I am not ready to commit myself to Iran. I have grown to love this amazing country and its wonderful people, but in my heart I long to return to State College. I have just heard from a friend that it is snowing there today.